This document discusses how transportation planning can impact public health and outlines best practices for conducting health impact assessments of transportation projects. It provides examples of how factors like the built environment, behaviors, and socioeconomic conditions influence health outcomes. The document advocates for an approach called "healthy community design" that aims to make communities more conducive to health by encouraging physical activity, social interaction and access to healthy foods through transportation and land use planning. It provides indicators that can be used to evaluate the health impacts of transportation projects and corridors. A case study from Massachusetts demonstrates how these principles were applied to a corridor study that assessed baseline health data and identified both contributions and barriers to public health in the project area.